We are presented with 6070 and 7664. Let's work out the sum.

Step 1: We'll start by adding the digits 0 & 4 in column 1 and get 4.

Step 2: We'll start by adding the digits 7 & 6 in column 2 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 0 & 6 in column 3 and get 7.

Step 4: We'll start by adding the digits 6 & 7 in column 4 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 6070 + 7664 = 13734.

